1. Field of the Invention
This invention relates to devices for holding and driving polygonal mirrors useful in devices such as nonmechanical printers and where the polygonal mirror is adjustably mounted to a drive shaft to allow for deviations of alignment of the drive shaft.
2. Prior Art
Polygonal mirrors are frequently used in modern technology. One known such use is found in nonmechanical and noncontact printers. In such devices, with the help of a light beam played on a photodconductive drum surface, an electrical latent image can be created of an image to be reproduced. The latent image is developed through the use of toner which is thereafter transferred to a final image carrier, for example a sheet of paper. The toner on the sheet of paper can thereafter be fixed through the application of heat and/or pressure.
In such constructions, it is possible for a laser to serve as the source for the light beam. The laser beam is directed to an acousto-optical beam deflector which splits the light beam into a series of beams positioned vertically one above the other. The series of beams are then directed to a rotating polygonal mirror which reflects them in a horizontal direction onto the photoconductive drum surface. A known arrangement for creation of electrical latent images with the aid of light beams which makes use of a polygonal mirror in the above manner is shown, for example, in U.S. Pat. No. 4,019,186, the teachings of which are herein incorporated by reference.
Deflection of the light beams by the polygonal mirror must be extremely precisely controlled in order to make satisfactory image production possible. This means that the polygonal mirror must be precisely aligned in its drive mounting. Since the drive mounting itself is subject to alignment difficulties, it must be possible to compensate for all such deviations from the desired true running of the drive by some adjustment means which allows proper adjustment of the mirror.